CROSS REFERENCES TO RELATED APPLICATIONS
The present application is a continuation application of U.S. patent application Ser. No. 12/208,137, filed on Sep. 10, 2008, which claims priority to U.S. Provisional Application No. 60/972,132, filed on Sep. 13, 2007, now abandoned, both of which are hereby incorporated by reference in their entireties.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
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OF THE INVENTION
1. Field of the Invention
The present invention relates to a golf club having an improved connection for interchanging components.
2. Description of the Related Art
In order to improve their game, golfers often customize their equipment to fit their particular swing. Golf equipment manufacturers have responded by increasing the variety of clubs available to golfers. For example, a particular model of a driver-type golf club may be offered in several different loft angles and lie angles to suit a particular golfer's needs. In addition, golfers can choose shafts, whether metal or graphite, and adjust the length of the shaft to suit their swing. Golf clubs that allow shaft and club head components to be easily interchanged facilitate this customization process.
One example is Wheeler, U.S. Pat. No. 3,524,646 for a Golf Club Assembly. The Wheeler patent discloses a putter having a grip and a putter head, both of which are detachable from a shaft. Fastening members, provided on the upper and lower ends of the shaft, have internal threads, which engage the external threads provided on both the lower end of the grip and the upper end of the putter head shank to secure these components to the shaft. The lower portion of the shaft further includes a flange, which contacts the upper end of the putter head shank, when the putter head is coupled to the shaft.
Another example is Walker, U.S. Pat. No. 5,433,442 for Golf Clubs with Quick Release Heads. The Walker patent discloses a golf club in which the club head is secured to the shaft by a coupling rod and a quick release pin. The upper end of the coupling rod has external threads that and engage the internal threads formed in the lower portion of the shaft. The lower end of the coupling rod, which is inserted into the hosel of the club head, has diametric apertures that align with diametric apertures in the hosel to receive the quick release pin.
Still another example is Roark, U.S. Pat. No. 6,547,673 for an Interchangeable Golf Club Head and Adjustable Handle System. The Roark patent discloses a golf club with a quick release for detaching a club head from a shaft. The quick release is a two-piece connector including a lower connector, which is secured in the hosel of the club head, and an upper connector, which is secured in the lower portion of the shaft. The upper connector has a pin and a ball catch that protrude radially outward from the lower end of the upper connector. The upper end of the lower connector has a slot formed therein for receiving the upper connector pin, and a separate hole for receiving the ball catch. When the shaft is coupled to the club head, the lower connector hole retains the ball catch to secure the shaft to the club head.
Two further examples are published applications to Burrows, U.S. Pub. Nos. 2004/0018886 and 2004/0018887, both of which are for a Temporary Golf Club Shaft-Component Connection. The Burrows applications disclose a temporary connection that includes an adapter insert, a socket member, and a mechanical fastener. The adapter insert, which is mounted on a shaft, includes a thrust flange. The socket member, which is mounted on the other golf club component (e.g., a club head), includes a thrust seat for seated reception of the thrust flange. The mechanical fastener (e.g., a compression nut or a lock bolt) removably interconnects the adapter insert and the socket member.
The prior art temporary head-shaft connections have several disadvantages. These connections typically add excessive weight to the club head, which affects the playability characteristics of the golf club. A change in the overall weight of a golf club alters the center of gravity and moments of inertias of the club head. Thus, a golf club with a shaft permanently affixed to a club head would have inherently different characteristics than a trial golf club that uses a prior art temporary connection to combine the same shaft and club head. In addition, many of these prior art connections are cumbersome to use. Some designs require the connection device to be accessed from the bottom of the club head, others from the top, with different tools and procedures for each.
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OF THE INVENTION
The present invention provides an improved club head-shaft connection that couples golf club heads and shafts in a manner that does not adversely affect the playability of the resulting golf club. The hosel of the club head is itself provided with a threaded portion and a rotation prevention portion. Therefore, fewer components are required for assembly, which reduces the overall weight of the connection and enables more discretionary weight to be distributed elsewhere in the club head.
In accordance with one embodiment of the invention, a golf club having removable components includes a club head, a shaft, and a connection assembly. The club head includes a body having a hosel. The hosel includes an upper treaded portion and a lower portion. The upper threaded portion of the hosel has a plurality of threads, which provide the upper threaded portion with a threaded cross-section. The lower portion of the hosel has a multi-faceted cross-section. The shaft has a tip end and a butt end. The connection assembly includes a sleeve mounted on the tip end of the shaft and a screw-cap. The sleeve has a body that includes a top section and a lower section. The lower section has a multi-faceted surface for engaging the lower portion of the hosel. The sleeve further includes an aperture for receiving the tip end of the shaft. The screw-cap has a body with a central aperture. The screw cap is mounted over the sleeve. The screw-cap body has an upper area and a threaded area, the latter of which capable of engaging the upper threaded portion of the hosel of the club head for removably securing the shaft to the club head.
In accordance with another embodiment of the invention, a golf club has a club head that includes a face cup and an aft-body. The face cup comprised of a metal material and including a striking face and a hosel. The hosel having an upper threaded portion and a lower portion. The upper threaded portion of the hosel has a plurality of threads thereon. The lower portion has a tapered, faceted cross-section. The golf club further includes a connection assembly comprising a sleeve and a screw-cap. The sleeve, which is mounted on the tip end of a shaft, includes a body having a top section and a lower section. The lower section of the sleeve has a tapered, multi-faceted surface for engaging the lower portion of the hosel. The sleeve further includes an aperture for receiving the tip end of the shaft. The screw-cap includes a body with a central aperture, the screw cap mounted over the sleeve, the body of the screw-cap having an upper area and a threaded area, the threaded area capable of engaging the upper threaded portion of the hosel of the club head for removably securing the shaft to the club head.
In a preferred embodiment, the lower section of the sleeve has three faceted surfaces. Once fully inserted into the hosel, the three sides of the sleeve will make contact with three mating surfaces designed in the lower portion of the hosel. Three sides are preferred to stop rotation both axially and around a pivot axis that is created when fewer than three contact points are achieved. When the screw-cap is tightened down on the sleeve, the screw-cap forces the multi-faceted lower section of the sleeve against the mating contact surfaces of the lower portion of the hosel of the golf club head, and all rotation is mechanically prohibited. This is superior to spline contact between the splines of a sleeve and those of a golf club head hosel, because there exists a small amount of axial slippage distance between the two splined surfaces. In addition, not having to machine the splines into the golf club head hosel provides cost savings.
Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a front plan view of a golf club in accordance with the present invention.
FIG. 2 is an exploded top perspective view of the golf club of FIG. 1 illustrating the various components, including a face cup portion of a club head, a shaft, and the connection assembly, which includes a sleeve and a screw-cap.
FIG. 3 is perspective view of the golf club of FIG. 2 in an assembled state.
FIG. 4 is a cross-sectional view taken generally along the line 4-4 of FIG. 3.
FIG. 5 is an enlarged cross-sectional view of a golf club shaft attached via the connection assembly to a hosel of a club head.
FIG. 6A is a top plan view of a face cup of a club head.
FIG. 6B is a cross-sectional view taken generally along the line A-A of FIG. 6A.
FIG. 6C is a cross-sectional view taken generally along the line B-B of FIG. 6B.
FIG. 6D is an enlarged sectional view taken along circle C of FIG. 6B.
FIGS. 6E-6H are enlarged sectional views showing greater details of an upper threaded portion of the hosel.
FIG. 7A is a plan view of a sleeve.
FIG. 7B is a cross-sectional view taken generally along the line A-A of FIG. 7A.